How to Restrict Microsoft Graph API Chat Access to Only Chats Involving a Specific User (User1)?

Hi Community,

I’m working on a Teams integration using the Microsoft Graph API at the service principal (app-only) level. I’m using the following endpoint to read chat messages:

GET https://graph.microsoft.com/v1.0/chats/{chat-id}/messages

My Goal:

I want to restrict access so that the app can only read messages from chats involving a specific user (User1). For example:

• Chats between User1 and User2
• Chats between User1 and User3
• But not chats between User2 and User3

Current Concern:

Using Chat.Read.All gives access to all chats in the tenant, which I want to avoid due to security and privacy concerns.

My Questions:

Is there a way to restrict Graph API access to only chats where User1 is a participant?

Can this be achieved using Resource-Specific Consent (RSC) permissions?

Is there any better approach or best practice to meet this requirement securely?

Any help, documentation references, or examples would be much appreciated.

Thanks in advance!